The Hario V60 takes its name from its 60-degree cone. This angle is no accident; it's the optimum geometry for water to flow through the coffee bed at an even rate. A wider cone lets water pass too quickly; a narrower one under-extracts.
A good cup rests on three things: the heat of the water, the size of the grind, and the rhythm of the pour. After boiling, let the water settle for a moment, hot but not boiling. Grind to the consistency of sea salt, neither powder nor coarse. A little coffee to generous water; a heaping tablespoon per cup is a good start.
Pour in three breaths. First, wet the grounds with a little water and watch them bloom; that swell is the simplest proof the beans are fresh. After a short pause, move the water from centre outward in slow, narrow circles. Leave the final pour to the middle.
Take your time. If the water drains too fast the cup falls flat; too slow and it turns bitter. Follow the flow with your eyes, not a timer. Pre-wetting the filter removes the papery taste and seats the cone fully against the glass.
One last tip: the V60 is an unforgiving brewer. Every variable directly affects the result. Change one thing at a time; never adjust both grind and water temperature at once.